Knowledgebase

Raspberry leaf curl #870484

Asked May 28, 2024, 5:30 PM EDT

Good afternoon, I have been watching our raspberry plants with concern. They started having leaves that curled, progressed to yellowing leaves and finally have become wilty yellow and curling. Both the floricanes and primocanes are effected with the primocanes becoming very yellow, wilted and sick looking, particularly in the inner parts of the row. One younger row is very heavily affected. A second, more established row is quickly following. A third row, not in the immediate area has patches of curled leaves. Obviously the past few weeks have been wet but the soil is loamy, the plants on a slope and there is no sitting water. I’m not an insect identifier, but I don’t see any leaf damage or eggs anywhere in the plants. Typically, our only insect pressure has been from Japanese beetles which I flick into water with a little dish soap. Right now, I believe we have a million white flies in the raspberry patch. I have looked at the articles on your website as well as Cornell. Is the Raspberry aphid a problem in Minnesota? If so, how do identify it? Unfortunately the pictures don’t document the problem very well. They show the curled leaves, but not the general malaise of the plants. We love our raspberries and want to help them be healthy and productive. Any help or insight you can provide would be greatly appreciated. Thank you.

Hennepin County Minnesota

Expert Response

Hi Marci,

How old is this planting? What is drainage like there? Is your soil heavy, or light? Does it seem very wet for a long time after all our rain?

Thanks.

MJ Replied May 30, 2024, 9:36 AM EDT
Hello, 
The most affected row of plants are 3-4 years old. Others are 4-5 years old. The rows are approximately 6-8 feet apart. 

The soil is great, pretty loamy and drains well. They are also on a slope so drainage isn’t a problem. While it is wet, it is no different than the nearby row that is affected as badly and there is definitely no standing water.  Hope this helps! Please let me know if you need more information. 

Thank you! 
Marci 
 

On May 30, 2024, at 8:36 AM, Ask Extension <<personal data hidden>> wrote:


The Question Asker Replied May 30, 2024, 11:29 PM EDT

Hi Marci,

Raspberries can have a ton of problems, and I don't have a definitive answer for you. I'm assuming this is not a watering issue, and will add links here that may help you eliminate issues one by one.

You may have seen this page on the Cornell website. These are the causes they list for wilting of both primocanes and floricanes:

https://blogs.cornell.edu/berrytool/raspberries/raspberries-both-primocanes-and-floricanes-are-wilting/

It's early in the season for signs of disease in raspberries. But check the canes for signs of the crown gall mentioned above.

This is a good U of M on viruses of backyard fruit. Note the recommendations at the bottom for handling an infected planting. 

https://extension.umn.edu/plant-diseases/viruses-backyard-fruit#symptoms-of-raspberry-leaf-curl-virus-1793861

Here's the U of M page on cane blight. This page also has control suggestions at the bottom of the page:

https://extension.umn.edu/plant-diseases/raspberry-cane-diseases

Borers are another possibility. Check your canes for these telltale punctures in the canes:

https://extension.unh.edu/resource/raspberry-cane-borer-fact-sheet

And here's a photo of a raspberry aphid. They're a pest mostly to black raspberries. Usually you can get rid of them with strong blasts of water to knock them to the ground, but other measures are mentioned here:

https://mastergardener.extension.wisc.edu/files/2018/10/aphids.pdf

I feel like I've overloaded you without solving your problem. My best suggestion would be to prune out the yellowing canes down to the ground. Do this on a dry day.

If you think this is virus related, you can submit a sample to the U of M Plant Disease Clinic. There is a charge.

https://pdc.umn.edu/

I hope this helps. Good luck.

MJ Replied May 31, 2024, 5:22 PM EDT

Loading ...